Methods

CNS-82

The 1982 China Nationwide Nutrition Survey covered 25 provinces
and three municipalities, all administrative units directly under the control of
central government with the exception of Tibet. A two-stage random sampling
method was used to select the survey households. Four to 20 survey sites were
chosen in each province/municipality by reference to its population size, and a
cluster of 50 households were randomly sampled from each selected survey site. A
total of 256 survey sites was finally chosen, including about 12000 households
and 71000 individuals of all ages. In addition 546 institutional feeding units
covering 166 000 individuals were surveyed, including factories, schools,
kindergartens and governmental institutions etc.

Household dietary data were collected for 5 consecutive days. The
change in the household inventory of food from the beginning to the end of the 5
survey days was assessed. This, and a weighed food survey of items used for
preparing meals every day, was adopted to determine the household and
institutional level of food consumption. Persons who participated in each meal
were recorded in order to calculate the per caput food consumption.

Height, weight, arm circumference and midarm skinfold were
measured in a portion of the sampled individuals. A clinical examination, blood
and urine tests were also carried out in a small portion of the sampled
subjects.

CHNS-89

The 1989 China Health and Nutrition Survey covered eight provinces
(Liaoning, Shandong, Henan, Jiangsu, Hubei, Hunan, Guangxi and Guizhou). A
multistage, random cluster process was used to draw the sample. Counties in the
eight provinces were stratified by income, and four counties were randomly
selected (one low-income, two middle-income and one high-income) in each
province. Within each county, the township capital was selected and three
villages were chosen randomly. In addition to the provincial capital, a
lower-income city from each province was also chosen. The whole sample consisted
of 188 primary survey sites, including 3780 households and covering about 16000
individuals.

Household food consumption was determined from changes in the food
inventory each day in combination with a weighing and measurement technique for
foods used by the household for 3 days. In addition, the individual dietary
intake was assessed on all children aged 1-6 years and on all adults aged 20-45
years for three consecutive days by a 24 h recall method.

Weight, height, arm circumference and midarm skinfold were
measured for adults aged 20-45 years (in subsequent rounds of this CNNS panel
the anthropometry of all age groups is being collected), and children's weight
and stature were
measured.